JP2001321720A - Method for making conductive film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for making a resin film in which the permeation of gas is controlled by a composite film comprising a resin layer and a conductive resin layer added with a conductive substance and which removes static electricity completely. SOLUTION: In the resin film, a clear layer (1) is formed on the surface of a metal base material (3), and a conductive film (2) added with the conductive substance (4) is formed on the clear layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin coating and a lining film on an inner surface of a stirring tank or a pipeline used mainly in a chemical factory or the like. Explosion, fire, damage,
It is intended to prevent such problems.

[0002]

2. Description of the Related Art Conventionally, when a conductive film is formed, (1) In the case of lot lining, a material having good conductivity such as carbon powder and metal powder is added to a resin to be 2-3 mm.
A conductive film having a thickness of 2 is formed by sintering. (2) Similarly, in the case of coating, a carbon powder, a metal powder, and the like are added to a resin, and a film of several hundred microns is formed by sintering to form a conductive film. In each case, a method of forming a conductive film with a single conductive layer and discharging static electricity generated inside the substrate from the inner surface to the outer surface of the substrate by passing through the film is generally used.

[0003]

(1) Layers of a coating or a lining film (hereinafter referred to as a resin film) are filled with conductive foreign substances and come into contact with each other to form a layer from the inner surface of the film to the back side of the film. It is connected. The static electricity is discharged by transmitting the foreign matter. However, the chemical solution or gas in the tube penetrates through the gap between the foreign substances, reaches the back side of the film, peels off the film, and starts corrosion of the base material.
As this progresses, electricity is cut off, and the static electricity generated on the base material is charged and ignites the flammable substance, causing a fire or explosion accident. There were drawbacks such as.

[0004] The present invention has been developed to solve these problems. The object of the present invention is to maintain the properties of chemical resistance, permeation resistance and permeation resistance as resin characteristics, and furthermore, An object of the present invention is to prevent explosion and fire accidents due to electrification by instantaneously releasing static electricity at the same time as the generation of static electricity, and at the same time, to prolong the life of equipment and provide a highly reliable and safe resin film.

[0005]

In order to achieve the above object, the present invention provides: (1) a non-conductive non-added resin layer is formed as a first layer on the inner surface of a metal substrate. (2) A conductive resin layer to which a conductive substance is added is formed as a second layer on top of another. (3) The end of the second layer film is short-circuited to the substrate at a place not in contact with the chemical solution, such as the outside of the substrate. A conductive resin coating and lining characterized by the fact that a two-layer film can be formed by this to obtain a film that has both the function of suppressing the penetration of chemicals and gases and the function of reliably discharging static electricity. It consists of how to make a film.

[0006]

According to the conductive resin film of the present invention, (1) Since the clear layer of the first layer is a pure and non-added film, it exhibits all the performances such as the chemical resistance as well as the permeation resistance of the resin. The result is a normal film. (2) A film to which a conductive substance is added is formed as the second layer, and the end is formed.

FIG. 5

As shown in FIG. 6, static electricity is completely adhered to the outer base material such as the flange and short-circuited.

Rather than escaping the resin film at right angles to the substrate as in FIG. 2,

As shown in FIG. 1, the effect of using the entire surface of the conductive layer film to flow reliably toward the short circuit portion in parallel with the film is produced. (3) Even if a chemical solution or gas permeates through the gap between the conductive materials of the second layer, it stops at the clear layer of the first layer, so that there is an effect that further penetration can be prevented. If the first layer and the second layer are the same raw material, they are completely fused, and delamination does not occur. (4) The conductivity can be freely changed by adjusting the addition rate of the conductive substance. Therefore, in pipes and devices that generate a large amount of static electricity, and in places where there is a high risk of ignition or explosion, etc. Danger can be further avoided by increasing the rate.
That's an excellent effect.

007

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described more specifically with reference to the drawings. First, FIG. 1 is an enlarged cross-sectional view of a two-layer conductive film showing an example of the present invention. In the figure, a first clear layer (non-added layer) is formed on the surface of a base material, and a conductive layer to which a conductive substance is added is formed as a second layer.

[0098]

[Example 1] (1) A fluororesin was applied to a metal tube base material having a length of 100A and a length of 500 mm with flanges at both ends by lot lining.

FIG. 3 is a sectional view of the same. At first,

[Figure 4] is masked with an iron plate over the entire circumference,
After the film was prevented from adhering, it was heated and fired with the first layer of the raw material without addition. Then

FIG. 5 shows that a clear layer of an integral film was formed up to the inner diameter portion connected to the entire inner surface of the tube. Then remove the masking,
A ring-shaped jig having an outer diameter was attached, and a space was formed between the inner diameter and the outer diameter so as to be a communicating part, and the conductive film to which the second-layer conductive material was added was fired. Then
The conductive layer of the integral film was formed up to the outer diameter portion connected to the entire inner surface of the tube. As a result, a two-layer coating having a pure clear layer was formed, although the appearance was a conventional conductive coating. And the conductive film

FIG. 4 shows a short circuit to the base material over the entire circumference of the substrate.
According to a continuity test by a tester, when the first layer was completed, it showed 1000 Mohm (no current), whereas the final completed film showed the same value of 0.9 Mohm from any point in the tube, It was confirmed that the substrate was short-circuited.

(2) Next, a polyethylene resin was applied to a substrate having the same dimensions and specifications as (1). The procedure was performed in exactly the same way. As a result, a good film was formed as in the case of the fluororesin. The continuity tests all showed the same numerical value, and it was confirmed that the inner surface of the film and the substrate were short-circuited.

[0010]

[Example 2] Next,

FIG. 7 shows an open iron round tank base material having an inner diameter of 500 mm and a depth of 700 mm, which was formed by a fluororesin thin film coating method. At first

FIG. 6 is a diagram showing the entire surface of the conductive portion is masked with an iron plate in the circumferential direction. Unheated raw materials were sprayed four times by electrostatic powder coating while heating, and heating and firing were repeated to form a clear layer. When the film thickness was measured at that time, 400
Micron values are shown. Next, after removing the mask and exposing the through-hole, the raw material to which the conductive substance was added was sprayed four times into the tank and the exposed part, and heating and firing were repeated. After the completion of the surface preparation, cooling was performed to form a conductive film.

As is clear from FIG. 6, the clear layer has reached the inner diameter of the flange, has no effect on the permeation of the solution in the tank, and the conductive film is formed between the inner surface of the tank and the base at the conductive portion of the flange. It can be confirmed that it is short-circuited. In addition, according to a continuity test by a tester, when the clear layer was completed, the value was 1000 M ohm, which was a value at which electricity did not flow.
Other parts showed a value of 0.9 Mohm. Thus, an advanced conductive film was formed.

[0011]

As is apparent from the above description, (1) Conventionally, the conductive film has a problem that "chemicals and gases are easily permeated". It can be said that it is natural because foreign substances are added to the resin. In other words, if the film is made of conductive material, the charge will be lost, but the film will be peeled off by gas permeation. Conversely, if the film is made of the resistance to permeation, the static electricity will not easily escape and cause an accident due to charging. At the site of use, he continued to be worried about that decision. However, according to the two-layer coating of the present invention, both problems can be solved at once. (2) In other words, an advanced composite film is formed that forms a permeation-resistant pure film on the lower clear layer to block gas permeation, forms a conductive film on the upper layer, instantaneously discharges and prevents charging. Because In addition, since it is possible to form a conductive film according to the actual conditions of the site, such as a stirring tank and a fluid that easily generates static electricity, it is possible to prevent fires and explosions due to static electricity and eliminate the fear of accidents. is there. (3) Further, even if a film is formed by a thermosetting resin or a general coating method, the same effect can be obtained according to the method of the present invention, so that it may be included in the present invention. As described above, according to the present invention, a number of excellent effects are exhibited, and it is convinced that accident prevention and protection of equipment in the chemical plant industry, as well as worker safety, can be greatly contributed. .

[0012]

[Brief description of the drawings]

FIG. 1 is a sectional view of a conductive film showing an example of the present invention.

FIG. 2 is a sectional view of a conductive film showing a conventional construction method.

FIG. 3 is a cross-sectional view of a metal pipe base material of Construction Example 1.

FIG. 4 is an end view thereof as viewed from the side.

FIG.

FIG. 3 is an enlarged view of a portion A of FIG.

FIG. 6 shows

FIG. 7 is an enlarged view of part B of FIG.

FIG. 7 is a cross-sectional view of a tank of Construction Example 2.

[Explanation of symbols]

 1. 1. Pure film without additives (clear layer) 2. Conductive film with conductive material added (conductive layer) Metal substrate 4. Conductive material Short circuit

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) B65D 90/04 B65D 90/04 B F16L 58/10 F16L 58/10 F term (reference) 3E070 AA02 AB01 AB09 AB31 BK01 DA01 MA02 3H024 EA01 EB01 ED07 EE01 4D075 AE03 CA22 CA42 CA44 DA15 DA19 DB01 DC05 EA02 EB13 EB16 EC60 4F100 AA37H AB01A AB01H AK01B AK01C AK04 AK17 BA03 BA10A BA10C CA21C DA11 DB09 J05 GB04 J04 GB04

Claims (1)

[Claims] (1) A nonconductive additive-free resin layer is formed as a first layer on the inner surface of a metal base material. (2) A conductive resin layer to which a conductive substance is added is formed as a second layer on top of another. (3) The end of the second layer film is short-circuited to the substrate at a place not in contact with the chemical solution, such as the outside of the substrate. A conductive resin coating and lining characterized by the fact that a two-layer film can be formed by this to obtain a film that has both the function of suppressing the penetration of chemicals and gases and the function of reliably discharging static electricity. How to make a film.